Intraosteal implants are widely used in dental restorations to support fixed or removable prostheses where the natural root of a teeth has been lost.
Schroeder et al. Oral Implantology, Georg Thieme Verlag Stuttgart and New York, 2nd edition, 1996, p. 128, relates to an implant to be inserted transgingivally into a jaw bone having an apically extending shank portion, on which there may be an external thread, and which terminates at the very bottom with an implant tip. The shank portion is adjoined by an implant neck which terminates at the very top with an implant shoulder which conically tapers coronally. To favor osseointegration, an additive and/or non-additive surface structuring is provided on the implant, the surface extending over the shank portion to a horizontal structure boundary situated on the implant neck. Thus, the boundary defines an interface between a bone tissue apposition surface of the implant and a soft-tissue apposition surface of the implant.
Apart from the problem of setting boundaries for the surface structuring on the coronal implant neck, there is also the problem of not allowing the implant shoulder to be visible when the implants are set while also optimally supporting the surrounding jaw bone. For implants set to an adequate depth, various abutments with anatomically adapted shaping have been proposed (see for examples DE 195 34 979 C1, DE 196 07 427 A1, DE 196 20 394 C1, U.S. Pat. No. 5,417,568 and WO 99/02102). In the case of semisubmerged implants and especially transgingivally set implants, there is also the risk however of incomplete coverage of the implant shoulder and consequently of aesthetic impairment.
To alleviate the above problems WO-A-01 49199, which was assigned to the assignee of the present invention and the content of which is herewith fully incorporated by reference, has proposed an intraosteal dental implant with an anatomically suitable conformation for aesthetic restoration, in particular, in the front teeth region. The known implant comprises an additive or a non-additive surface structure, in order to favor osteal integration, the surface structure extending over the shank section up to a structure boundary or interface on the neck of the implant. The structure boundary falls anteriorly in the apical direction to a low point and rises, on the proximal implant edge, to a high point. The shoulder of the implant is anatomically formed to follow the boundary or interface such that, on the interdental side surfaces, raised regions exist and, on each of the anterior and posterior implant edges, recessed regions exist.
The above described prior art dental implants, however, are not readily accessible in the palatal or in the lingual area to the implantologist.